You just pull, sometimes you have to do a little wiggling back and forth. When you find that button (it is small) and consists of a metal cap with a spring around it, you should be able to get it out fairly easy.
1953 Chevrolet 3600 Fried Green T'mater (Vern) In the Stovebolt Gallery Caution: Political Statement Man who runs in front of car gets tired, man who runs behind car gets exhausted.